Abstract
SummaryInducible promoters such as Plac are of limited usability for industrial protein production with Pseudomonas putida. We therefore utilized cell density‐dependent auto‐inducible promoters for recombinant gene expression in P. putida KT2440 based on the RoxS/RoxR Quorum Sensing (QS) system of the bacterium. To this end, genetic regions upstream of the RoxS/RoxR‐regulated genes ddcA (PR ox132) and PP_3332 (PR ox306) were inserted into plasmids that mediated the expression of superfolder green fluorescent protein (sfGFP) and surface displayed mCherry, confirming their promoter functionalities. Mutation of the Pribnow box of PR ox306 to the σ70 consensus sequence (PR ox3061) resulted in a more than threefold increase of sfGFP production. All three promoters caused cell density‐dependent expression, starting transcription at optical densities (OD 578) of approximately 1.0 (PR ox132, PR ox306) or 0.7 (PR ox3061) as determined by RT‐qPCR. The QS dependency of PR ox306 was further shown by cultivating P. putida in media that had already been used for cultivation and thus contained bacterial signal molecules. The longer P. putida had grown in these media before, the earlier protein expression in freshly inoculated P. putida appeared with PR ox306. This confirmed previous findings that a bacterial compound accumulates within the culture and induces protein expression.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
